Vibration insulating handle

Abstract

A vibration insulating handle for a pneumatic power tool comprising an inner tube (15) and an outer tube (16) both rigidly but adjustably attached to the tool housing (10). The inner tube (15) forms an air exhaust passage (13) which communicates with a silencer (12) carried on the extreme end of the outer tube (16). The tubes (15, 16) are radially spaced relative to each other leaving an annular heat insulating gap therebetween. A weakened portion (30) on the outer tube (16) is located adjacent the tool housing end of the latter and comprises two axially spaced pairs of peripherally extending slots (27, 28). The weakened portion (30) enables the outer tube (16) to yield elastically in radial directions to bending and shearing vibration forces transmitted to the handle during operation of the tool.

I claim: 
     
       1. A vibration insulating handle to be mounted on the housing of a portable power tool, comprising: an inner tube element rigidly attached at one end to a part of the tool housing;   a grip tube element coaxially surrounding said inner tube element and defining together with said inner tube element an annular gap which extends over a substantial part of the axial lengths of said inner and said grip tube elements;   said grip tube element being rigidly attached to a part of the tool housing at one end and being rigidly connected to said inner tube element at an opposite free end, said grip tube element being provided with a number of circumferentially extending through slots in the vicinity of its one end attached to the housing;   wherein said through slots form a weakened portion of said grip tube element to enable elastic yield of said grip tube element in the radial direction relative to said inner tube element in response to bending and shearing vibration forces transmitted from the tool housing, said weakened portion maintaining resistance to torsional loads applied to said grip tube element during operation of the power tool to avoid impairment of handling of the tool.   
     
     
       2. Handle according to claim 1, wherein said slots are arranged in at least two parallel axially spaced rows, such that portions of the slots in one row are circumferentially coextensive with the slots in the next row. 
     
     
       3. Handle according to claim 2, wherein said inner tube element forms an air communication passage for a pneumatically powered tool. 
     
     
       4. Handle according to claim 3, including a silencer mounted at the free end of said grip tube element and wherein said air communication passage is an exhaust passage for communicating with said silencer. 
     
     
       5. Handle according to claim 1, wherein said inner tube element forms an air communication passage for a pneumatically powered tool. 
     
     
       6. Handle according to claim 5, including a silencer mounted at the free end of said grip tube element and wherein said air communication passage is an exhaust passage for communicating with said silencer.